Frontend Developer

Senior Frontend Engineer (React/TypeScript) SC Cleared (MOD)

3-month contract (extendable)

550600/day

Outside IR35

Hybrid Thames Valley

Join a cutting-edge UK-based AI company building intuitive, high-performance interfaces for generative AI platforms. Were seeking a Senior Frontend Engineer to lead the development of user-facing experiences that make advanced AI capabilities accessible, elegant, and production-ready.

This is a unique opportunity to shape the frontend architecture of secure, scalable AI systems deployed in regulated sectors. Youll work across product, backend, and AI teams to deliver performant, responsive web applications with real-time streaming capabilities.

The Role:

• Ownership of frontend architecture for AI-driven chat platforms, from design to deployment
• Development of scalable SPAs using React 19, TypeScript, and Vite for optimal performance
• Implementation of authentication flows with Azure MSAL/OAuth2 and secure session handling
• State management using Zustand and TanStack Query for seamless client-server sync
• Integration of streaming AI endpoints via AI SDK React, including WebSocket handling and graceful degradation
• Deployment via Docker containers with multi-stage builds and CI/CD pipelines using GitHub Actions
• Collaboration with DevOps for AWS CloudFront/S3 delivery, caching, and CDN optimization
• Accessibility leadership (WCAG 2.1 AA), cross-browser testing, and performance monitoring via Web Vitals
• Security-first development including CSP headers, XSS prevention, and secure API communication
• Mentorship and technical leadership across frontend best practices and performance optimization

Experience Required:

• Active SC clearance for MOD work
• 5+ years of frontend development with React and TypeScript in production environments
• Proven experience building complex SPAs with modern routing and state management
• Deep understanding of browser APIs, performance optimization, and responsive design
• Familiarity with Vite, pnpm, Git workflows, and OpenAPI integration via tools like Orval
• Experience with WebSockets, real-time data handling, and secure API communication
• Strong communication skills and ability to mentor and influence frontend standards

This role is urgent and interviews can be arranged quickly. If youre ready to lead frontend delivery at the intersection of AI and user experience, and you hold SC clearance (MOD), apply now for immediate consideration.

DISCLAIMER: No terminology in this advert is intended to discriminate on the grounds of age, sex, race, religion or belief, disability, pregnancy and maternity, marriage and civil partnership, sexual orientation, gender, and/or gender reassignment. We welcome applications from all qualified candidates. Attis Global Limited operates as an employment business and agency.

Keywords for search: React Frontend Engineer, SC Cleared Contractor, AI UI Developer, TypeScript SPA Architect, Secure Chat Platform, Vite Build Expert, WebSocket Integration, OAuth2 Auth Flow, Real-Time UI Developer, Accessibility Lead, GitHub Actions CI/CD, AWS CloudFront Deployment, Streaming AI Frontend, Regulated Sector UI, CSP/XSS Secure Frontend